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101.
Imaging studies are a major component in the evaluation of patients for the screening,staging and surveillance of colorectal cancer.This review presents commonly encountered findings in the diagnosis and staging of patients with colorectal cancer using computed tomography(CT)colonography,magnetic resonance imaging(MRI),and positron emission tomography(PET)/CT colonography.CT colonography provides important information for the preoperative assessment of T staging.Wall deformities are associated with muscular or subserosal invasion.Lymph node metastases from colorectal cancer often present with calcifications.CT is superior to detect calcified metastases.Three-dimensional CT to image the vascular anatomy facilitates laparoscopic surgery.T staging of rectal cancer by MRI is an established modality because MRI can diagnose rectal wall laminar structure.N staging in patients with colorectal cancer is still challenging using any imaging modality.MRI is more accurate than CT for the evaluation of liver metastases.PET/CT colonography isvaluable in the evaluation of extra-colonic and hepatic disease.PET/CT colonography is useful for obstructing colorectal cancers that cannot be traversed colonoscopically.PET/CT colonography is able to localize synchronous colon cancers proximal to the obstruction precisely.However,there is no definite evidence to support the routine clinical use of PET/CT colonography.  相似文献   
102.
Dahl salt-sensitive (Dahl-S) rats, serving as a model of hereditary hypertension, were used to examine the effect of mannooligosaccharides (MOS) on blood pressure. Dahl-S rats were induced to develop hypertension by administering them with a 1.25% salt solution ad libitum. In a 10-wk experimental period, the Dahl-S control and MOS groups developed and maintained significantly higher blood pressure than the Dahl salt-resistant normal control group. The MOS group showed a significantly lower blood pressure than the Dahl-S control group after 5-wk of treatment (p<0.05). In addition, the serum aldosterone level of the MOS group significantly decreased (p<0.05). The findings of this study using a model of hypertensive rats suggest that MOS are able to suppress an elevation in blood pressure.  相似文献   
103.

Background/purpose

Congenital diaphragmatic hernia (CDH) remains a defiant challenge for pediatric surgeons. Since 2003, we developed a new protocol aiming for the better outcome. In this study, the usefulness of our new protocol was evaluated.

Materials and methods

Forty-six neonates with CDH at the age of less than 24 h were divided into two groups based on the difference of era and treatment protocols. In Group 1, 15 patients were treated between 1997 and 2002 and 31 patients were treated between 2003 and 2011 in Group 2. In the latter group, a new protocol was introduced focusing on the prevention of lung edema as well as lung injury by steroid administration and on the stabilization of cardiopulmonary function using continuous d-mannitol infusion. The survival rate and the postoperative intubation period (POIP) were compared between the two groups.

Results

The overall survival rate was significantly increased from 53 % (8/15) to 81 % (25/31) (p < 0.05). In isolated CDH, the survival rate was increased from 58 to 93 %. The average POIP was remarkably shortened from 39.0 to 4.4 days (p < 0.01).

Conclusion

Our new protocol remarkably improved the survival rate and shortened the period of mechanical ventilation in neonates with CDH.  相似文献   
104.
In the nervous system, influx of calcium and chloride ions into neurons regulates the signaling system by excitation and inhibition, respectively. In this study, we demonstrated the effects of the ion influx into epidermal keratinocytes in the permeability barrier repair process of the skin after damage. Topical application of the neurotransmitters glutamate and nicotine, which activate the calcium channel in neurons, delayed the barrier repair after tape stripping. In contrast, the neurotransmitters GABA and glycine, which activate the chloride channel in neurons, accelerated barrier repair. Topical application of the calcium ionophore ionomycin delayed barrier recovery and chloride ionophore 1 accelerated barrier repair after barrier disruption by tape stripping and acetone treatment. Ionomycin increased the intracellular calcium concentration in cultured keratinocytes whereas the chloride ionophore 1 increased the intracellular chloride ion concentration. In vivo light microscopy and electron microscopy observation showed acceleration of the exocytosis of lipid-containing lamellar bodies by the chloride ionophore and delay of the exocytosis by the calcium ionophore. These results suggest that, like the nervous system, influx of calcium and chloride ions into epidermal keratinocytes through ionotropic receptors plays a crucial role in cutaneous barrier homeostasis.  相似文献   
105.
Sister Mary Joseph’s nodule (SMJN), which is known as a malignant tumor metastasized to the umbilicus, is a rare condition. We report ultrasonic findings of SMJN secondary to ovarian cancer in a 66-year-old woman. The umbilical tumor was observed as a hypoechoic mass with punctate hyperechoic foci. A pathological specimen obtained by needle biopsy confirmed adenocarcinoma with psammoma bodies. A comparison of the ultrasonographic findings with the pathological findings of the resected specimen suggested that the hyperechoic foci corresponded to psammoma bodies. When hyperechoic foci are observed inside SMJN by ultrasonography, adenocarcinoma from ovarian cancer should be included in the differential diagnosis.  相似文献   
106.
It is well known that dermal papilla cells (DPCs) play crucial roles in hair follicle induction. In this study, we examined whether Wnt/β-catenin activation results in maintenance of the hair-inducing ability of human DPCs. Expression of DPC marker genes was maintained under Wnt/β-catenin signalling stimulation by GSK-3β inhibition. Furthermore, human DPCs showed constant hair induction when transplanted with murine epidermal cell fraction. Alu-positive human DPCs were essentially detected adjacent to the reconstructing epidermal structure positive for P-cadherin immunoreactivity. The transplanted human DPCs were abundant in the surrounding dermal sheath portion of the fully regenerated hair follicles. These results support the importance of Wnt/β-catenin signalling in hair follicle induction. This study may provide valuable information to establish a culture method of human DPCs for cell-based therapy.  相似文献   
107.
Glioblastoma multiforme (GM), the most frequent primary malignant brain tumor, is highly invasive due to the expression of proteases, including urokinase-type plasminogen activator (uPA). Here, we show the potential of our new and powerful recombinant Sendai virus (rSeV) showing uPA-specific cell-to-cell fusion activity [rSeV/dMFct14 (uPA2), named “BioKnife”] for GM treatment, an effect that was synergistically enhanced by arming BioKnife with the interferon-β (IFN-β) gene. BioKnife killed human GM cell lines efficiently in a uPA-dependent fashion, and this killing was prevented by PA inhibitor-1. Rat gliosarcoma 9L cells expressing both uPA and its functional receptor uPAR (9L-L/R) exhibited high uPA activity on the cellular surface and were highly susceptible to BioKnife. Although parent 9L cells (9L-P) were resistant to BioKnife and to BioKnife expressing IFN-β (BioKnife-IFNβ), cell–cell fusion of 9L-L/R strongly facilitated the expression of IFN-β, and in turn, IFN-β significantly accelerated the fusion activity of BioKnife. A similar synergy was seen in a rat orthotopic brain GM model with 9L-L/R in vivo; therefore, these results suggest that BioKnife-IFNβ may have significant potential to improve the survival of GM patients in a clinical setting.  相似文献   
108.
Fear is one of the most potent emotional experiences and is an adaptive component of response to potentially threatening stimuli. On the other hand, too much or inappropriate fear accounts for many common psychiatric problems. Cumulative evidence suggests that the amygdala plays a central role in the acquisition, storage and expression of fear memory. Here, we developed an inducible striatal neuron ablation system in transgenic mice. The ablation of striatal neurons in the adult brain hardly affected the auditory fear learning under the standard condition in agreement with previous studies. When conditioned with a low-intensity unconditioned stimulus, however, the formation of long-term fear memory but not short-tem memory was impaired in striatal neuron-ablated mice. Consistently, the ablation of striatal neurons 24 h after conditioning with the low-intensity unconditioned stimulus, when the long-term fear memory was formed, diminished the retention of the long-term memory. Our results reveal a novel form of the auditory fear memory depending on striatal neurons at the low-intensity unconditioned stimulus.  相似文献   
109.
The effect of a novel thromboxane A2 receptor (TP) antagonist, (+/-)-sodium[2-(4-chlorophenylsulfonylaminomethyl)- indan-5-yl]acetate monohydrate (Z-335), on the U46619-induced responses was compared between rabbit platelets and aorta. Z-335 inhibited platelet shape change induced by U46619 with higher efficacy than SQ29548, a common TP antagonist. The U46619-induced platelet aggregation was inhibited by Z-335 in a noncompetitive manner, while it was competitively inhibited by SQ29548. Z-335 inhibited U46619-induced vasoconstriction of rabbit aorta with higher efficacy than SQ29548. The pA2 value of Z-335 in aortic vasoconstriction was significantly higher than in platelet shape change. The competitive binding study showed the higher pKi value of Z-335 against [3H]-SQ29548 binding in rabbit aortic smooth muscle cells than in platelets. These data suggest that Z-335 has useful characteristics of TP antagonism.  相似文献   
110.
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